Wrench with self-adjusting jaws



Nov. 21, 1950 E. L. MANSPEAKER 2,531,285

WRENCH WITH SELF-ADJUSTING JAWS Filed March a, 1%;

Edward L. Manspea/rer INVENTOR.

BY z m Patented Nov. 21, 1950 UNITED STATES PATENT OFFICE WRENCH WITH SELF-ADJUSTING JAWS Edward L. Manspeaker, Turtle Creek, Pa.

Application March 8, 1948, Serial No. 13,539

Claims. 1

This invention relates to new and useful improvements and structural refinements in wrenches, pliers or similar tools used for turning, gripping, bending or otherwise handling the work, and the principal object of; the invention is to assure firm and secure gripping action of the jaws of the tool on the Work, notwithstanding the size or thickness of the latter.

This object is achieved in the invention by employing resilient means for closing the jaws on the work, means for locking the jaws thereon, and additional means which is responsive to the actuation of the second means and is dependent upon the thickness of the work, whereby the relative. locking position of the jaws may be preadjusted. In other words, if a piece of work is inserted between the jaws of the wrench, the jaws will resiliently close thereon, whereupon by simply actuating the handles of the wrench, the jaws will be firmly and securely locked on the work, regardless of the thickness or size of the latter.

An important feature of the invention resides in providing adjusting means whereby pressure of the locked, jaws on the work may be varied as desired, in accordance with the hardness of the material being handled Another feature of the invention lies in its simplicity of construction, convenience of maniplation, and accuracy and dependability in the performance of its function.

With the above more important objects and features in view, and such other objects and features as may become apparent as this specification proceeds, the invention consists essentially of the arrangement and construction of parts as illustrated in the accompanying drawings, in which:-

Figure lis a side elevational view of the invention, partially broken away to reveal its construct-ion.

Figure 2 is a further side elevational view, similar to that shown in Figure 1, but illustrating a piece of work between the jaws.

Figure 3 is a cross-sectional view, taken substantially in the plane of the line 3-3 in Figure 1.

Figure 4 is a cross-sectional view, taken sub stantially in the plane of the line 4-4 in Figure 1.

Figure 5 is a cross-sectional view, taken substantially in the plane of the line 5-5 in Figure 2, and

Figure 6 is a cross-sectional view, taken sub- 2 stantially in the plane of the line 6-6 in Figure 2. I

Like characters of reference are employed to designate like parts in the specification and throughout the several views.

Referring now to the accompanying drawings in detail, the invention consists of a wrench designated generally by the reference character Ill, the same embodying in its construction an elongated body lZ, one end portion of which constitutes a handle M, while the remaining end portion of the body is formed with a stationary gripping jaw I6.

The mid-portion of the body i2 is of a substantially U-shaped cross-sectional configuration as illustrated at iii in Figures 3 and 4, while the handle portion 14 of the body is of a hollow,

substantially tubular character, terminating in,

a closed end wall 20.

A plate 22 carrying a further jaw 24 is movably disposed in the U-shaped mid-portion l8 of the body IE, to which it is attached by means of a transversely extending pivot pin 26. The jaw 24, which may be referred to as a movable jaw, coacts with the stationary jaw It, as will be clearlv apparent.

A handle 28 has a portion 30 at one end thereof which is of a U-shaped cross-sectional configuration and straddles a corner of the plate 22, being pivotally attached thereto by means of a pin 32. A further pin 34 extends transversely through the U-shaped portion 35 of the handle 28, the pin 34 terminating at both ends in enlarged heads 36, as is best shown in Figure 3.

A link 38, configurated substantially as shown, is pivotally mounted at one end portion thereof on the pin 34, this end portion being formed with a series of steps 4E! and a protruding lug 42, the purpose of which will be more fully hereinafter described.

A suitable spring 44 engages a notch 46 formed in the link 38 and straddling the opposite sides of the link, the spring M passes around the pin 3d and the end portions thereof bear against the handle 28, as shown at 48, whereby the link 38 is urged in the direction of the arrow 50 in Figure 1.

A further spring 52 passing through an aperture formed in the link 38 and engaging a notch or seat 54 with which the link is provided, bears against the inner surface of the body l2, the spring 52 being somewhat weaker with respect to theaforementioned spring M, but nevertheless being sufficiently strong to urge the adjacent end portion of the link 38 upwardly, when the handles I 4, 28 are in their spread position, as shown in Figure 1.

The link 38 terminates in a yoke 56, the latter accommodating a pivot pin 58 whereby the link 38 is pivotally attached to a lever 60.

The latter is, in turn, connected to a locking unit 62 including a pair of juxtaposed wedges 64, 66, these two wedges being slidable in unison in the elongated recess 68 with which the handle portion I4 of the body I2 is formed.

The wedge 64 is formed with a recess to accommodate an end portion of .the lever 60 which is pivotally connected to the wedge 64 by means of a transversely extending pin I0, the lever 60 being equipped with a laterally projecting detent I2 which engages a recess I4 formed in the wedge 66.

If desired, the upper surface of the wedge 66 may be milled or knurled as at 16, and it will be also noted that the minor end of the wedge 64 terminates in an integrally formed pressure pad I8 disposed adjacent the major end of the wedge 66, while a compression spring 80 is interposed between the pad 78 and the closed end of the handle I4, as will be clearly apparent from the accompanying drawings.

Finally, a stop bar 82, carried by a pin 84 provided with a control button 86, is disposed on the U-shaped portion of the handle 23, the pin 84 being slidable in a slot 88 with which the portion 30 of the handle is formed, and the portion 30 being equipped with a series of notches 90 to selectively receive the pin or bar 82. A suitable spring 92 is positioned between the handle portion 30 and the knob 86, whereby the pin or bar 82 is urged in engagement with the notches 90, as will be clearly apparent.

Having thus described the construction of the invention, its method of operation will now be explained. Assuming the wrench to be in the position shown in the accompanying Figure l, the compression spring 80, by exerting pressure upon the locking unit 62 (which is normally freely slidable in the recess 68), will urge the lever and the link 38 in the general direction of the arrow 64, thereby urging the movable jaw 24 in engagement with the stationary jaw I6.

However, if a piece of work, such as for example, that illustrated at 96 in Figure 2, is to be gripped by the jaws I6, 24, the jaws are separated against the resiliency of the spring so as to facilitate insertion of the work therebetween whereupon the spring 80 will close the jaws onto the work, as shown in the left-hand portion of Figure 2.

The work piece may be firmly and securely clamped between the jaws by simply moving the handle 28 toward the handle I4, at the commencement of which action the link 33 will be swung in the direction of the arrow 50 while the lever 68 will move in the direction of the arrow 66, during which movement, the detent l2, by engaging the recess 74, will slide the wedge 66 in the direction of the arrow 98 (the wedge 64 remaining relatively stationary), so that the perimeter of the locking unit 62 will be expanded, so to speak, as will be clearly apparent. This expanding action of the locking unit will cause the same, particularly the milled portion 76 thereof, to firmly and securely lock itself by frictional engagement in the recess 66,

Thereupon, as the handle 28 continues to be pressed toward the handle I4, further sliding movement of the locking unit 62 in the handle I4 will not be possible, and as a result, the plate 22 will be urged in the direction of the arrow I00, as will be presently described.

As is shown in Figure 1, the pivot 34 is laterally offset from an imaginary line I02 connecting the pivots 32 and 58, matters being so arranged that when the unit 62 becomes locked in the handle I 4, the axis of the pivot 34 is substantially on the line I02. However, as the movement of the handle 28 toward the handle I4 continues, the pivot 34 will pass to the other side of the line I02 (as shown in Figure 2), whereby a toggle action will result, locking the jaws 24, I6 against the work piece 06. It is of particular interest to note that by virtue of the slidable disposition of the unit 62 in the recess 68, this locking action of the jaws will be effected regardless of the thickness of the work piece, the sliding action of the unit 62 compensating for the thickness of the work piece, so to speak, so that the locking of the jaws I6, 24 does not begin until after the pivot 34 has passed beyond the line I02.

t is also to be noted that when the jaws I6, 24 are in their locked position on the work piece 96, the lug 42 of the link 38 will engage the inner surface of the handle 28, substantially as shown in Figure 2.

Finally, the wrench includes means for varying the amount of pressure exerted by the jaws I6, 24 onto the work piece 96, so that the amount of pressure so exerted may be varied in accordance with the hardness of the material being handled. The means, that is, means for varying the jaw pressure, assumes the form of the afore mentioned control knob or button 86, which may be slid so as to place the stop pin or bar 82 in any one of the notches 90.

The bar 82 is engageable with the steps 40 of the link 38, depending upon the particular one of the notches in which the bar 82 is disposed, so that by sliding the knob 86 from right to left before the piece 96 is inserted between the jaws I 6, 24, the locking unit 62 will be correspondingly slid from right to left by the spring 60, thereby tending to separate the jaws I6, 24 to some extent, so that when the handles I4, 28 are brought together for the purpose of locking the jaws, the jaws will be somewhat further apart and lesser pressure will be exerted upon the work piece.

It should be also explained that preparatory to the positioning of the work piece between the jaws I6, 24, the jaws may be separated by holding the handle I4 in one hand and pressing either of the enlarged heads 36 of the pin 34 with the forefinger of the same hand in the general direction of the arrow I04, whereby separation of the jaws will be facilitated.

It is believed that the advantages and use of the invention will be clearly apparent from the foregoing disclosure and accordingly, further description thereof at this point is deemed unnecessary.

While in the foregoing there has been shown and described the preferred embodiment of this invention it is to be understood that minor changes in the details of construction, combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as claimed.

Having described the invention what is claimed as new is:

1. In a wrench, the combination of a handleforming body provided at one end with a stationary jaw and formed with an elongated recess, a coacting movable jaw pivoted to said body, a

second handle pivoted to said movable jaw, an expansible and contractible locking unit including a pair of juxtaposed wedges slidable in unison in said recess, means for sliding said wedges one with respect to the other, and toggle linkage operatively connecting said locking unit to said second handle.

2. The device as defined in claim 1 together with resilient means for closing said jaws on the work, compression of said handles locking said unit in said body and thereafter locking said jaws.

3. A wrench comprising a handle-forming body provided at one end with a stationary jaw and in its remaining end portion with an elongated recess, a coasting movable jaw pivoted to said body, a second handle pivoted to said movable jaw, an expansible locking unit including a pair of juxtaposed wedges slidable in unison in said recess, a link pivoted to said second handle, a lever pivoted to said link and to one of said wedges, a detent on said lever operatively engaging the second wedge, and resilient means for closing said jaws on the work.

4. The device as defined in claim 3 together REFERENCES CITED The following references are of record in the filo of this patent:

UNITED STATES PATENTS Number Name Date 952,079 McIntire Mar. 15, 1910 2,312,947 Westman Mar. 2, 1943 2,463,721 Spencer et al Mar. 8, 1949 2,471,734 Fischer May 31, 1949 2,487,281 Steckelberg Nov. 8, 1949 

